Content management systems are used to administer business information, including text, image, video and web content. Such systems typically provide strict access control for managed content. Users and groups can be defined with rights to create, retrieve, update, and delete content, for example. Examples of commercial enterprise content management products include IBM DB2 Content Manager (referred to hereafter simply as Content Manager), Documentum [Doc] and FileNet Content Manager [FileN]. Content Manager is an enterprise content management system which provides an infrastructure for business information management [Her03]. Content repository services include capture, creation, organization, workflow, archival and lifecycle management.
Delivery of such content to users could be enhanced by using a proxy cache to minimize network bandwidth and improve the quality of service for users. The same cached content can be delivered to multiple users or to a given user multiple times by the proxy without the need to contact a back end server. Proxy caches are typically deployed as forward proxy servers, reverse proxy servers or transparent proxy servers; thus cached content can be placed in the network closer to the users or in front of back-end content servers in order to reduce the load on these servers. There are numerous public domain and commercial web caching proxies available today including Cern-httpd [LNB-L], Squid [SWPC], Harvest [CDNSW96], Jigsaw [Jigsaw], IBM WebSphere Edge Server [WSES], Inktomi Traffic Server [ITS] and NetCache [Danzig98]. A listing of web proxy caches can be found in [Davison].
However, the proxy cache needs to be aware of and enforce any access control rules defined in the content management system for content that originates in the content management system but is cached by the proxy server. For example, assume a company serves three tiers of clients: platinum, gold, and silver. The content management system might store content which should only be visible to the platinum customers. If such content is cached, the proxy server must ensure that this content can not be retrieved by a silver customer.
A content management system that is integrated with a web caching proxy so that content under the control of the content management system is delivered to users from the proxy cache according to specified access control rules is therefore needed.